Percutaneous intervention versus coronary bypass surgery for patients older than 70 years of age with high-risk unstable angina.

BACKGROUND

The Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) study was a multicenter Veterans Affairs randomized trial and registry that compared long-term survival of percutaneous coronary intervention with coronary artery bypass graft surgery for the treatment of patients with medically refractory myocardial ischemia and at least one additional risk factor for an adverse outcome with bypass. Both the randomized trial and the registry demonstrated comparable 3-year survival. The purpose of this study was to compare bypass and percutaneous intervention survival of AWESOME patients who were older than 70 years of age.

METHODS

Over a 5-year period (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of the following five risk factors (prior heart surgery, myocardial infarction within 7 days, left ventricular ejection fraction less than 35%, age > 70 years, intraaortic balloon pump requirement to stabilize) were identified. Of these patients, 1,278 were older than 70 years of age. Eight hundred, seventy-one patients were turned down by at least one physician, 407 were acceptable to both physician and surgeon for randomization, and 236 (60%) consented to randomization. Of the 1,042 eligible patients who were not randomized, 871 had their revascularization directed by a physician who was not involved in the study. One hundred, seventy-one patients who were acceptable for randomization by both the interventional cardiologist and the cardiac surgeon refused consent.

RESULTS

Bypass and percutaneous intervention survival were compared using Kaplan-Meier curves and log rank tests. Bypass and percutaneous intervention 36-month survival rates for patients older than 70 years of age were 76% and 75%, respectively, among the eligible patients. Survival was 71% and 78% among those patients who were randomized and 76% and 67% in the physician-directed subgroup. Of those patients who chose their revascularization techniques, the survivals were 79% and 85%, respectively. The survival differences are not large, and none of the global log rank tests of bypass compared with percutaneous intervention survival showed a statistically significant difference over 5 years.

CONCLUSIONS

Both the randomized and registry subgroups of patients who were older than 70 years of age support the trial conclusions that either bypass or percutaneous intervention effectively relieves medically refractory ischemia among high-risk unstable angina patients whose age was greater than 70 years.